Calculator



Dec. 8, 1942. H. a. ANDERSON CALCULATOR Filed June 19, 1940 @l (,pEs/REDM/LEAGE F,...-

INVENTOR.

Patented Dec. 8, 1942 Unirse sra'rss PATENT OFFICE.

Claims.

The present invention relates to calculators of the type having relatively slidable members provided with registrable arithmetical indicia or numerals and windows for selectively exposing them.

Among the objects of the invention is to provide in a calculator of the character disclosed a novel device comprising a holder provided with rithmetrical indicia or numerals on a wall thereof and a window in the other wall thereof and opposite such indicia, and having relatively slidable sliders with crossing or traversing elongated windows slidable between such indicia and window to provide a shifting window common to the two elongated crossing windows for selectively exposing indicium of such indicia. Adjacent the rst mentioned window, preferably, there are indicative indicia or numerals with which an arrow on a slider is selectively registrable as such slider is slid.

The elongated windows are at an acute angle to each other and also at acute angles to the line of slide of the sliders. The indicia first mentioned above are arranged in crossing rows, with the rows traversing in one direction being at an acute angle to the rows traversing in the other direction. Each indicium is common to two crossing rows.

The invention, in particular, is useful to show quickly and without usual calculating the saving that may be had, as for example, by the owner of an automobile, when certain assumed improvements or adjustments are effected to improve the efficiency and operation of the automobile. To illustrate, the calculator ci this invention may be set to the values known to exist in the automobile engine intended to be improved, and then adjusting the calculator to show what saving can be made il the improvement in the engine operation be made as assumed.

Assuming the average cost of fuel to be 19 per gallon, and basing the calculation on 5,000 miles of travel, a slider is slid to show the then existing mileage by bringing it in registry with the window therefor. For example, if the mileage is 12 miles per gallon, the indicium l2 is exposed at the corresponding window. In other windows will appear the total number of gallons used, namely, L116 gallons in the illustrative example, and the total cost of $79.00 in a further window.

The calculator is turned over and a slider carrying an arrow is slid to bring the arrow Iin register witlr an indicative indicium #for the desired mileage as, for example, 16 miles per gallon. In the common window ci the two elongated windows will be exposed indicium 20, showing a saving of $20.00 by the proposed improvement. This is merely one of rthe examples to illustrate the utility of the device.

Other objects, advantages, capabilities and features are comprehended by the invention, as will later appear and as are inherently possessed by the invention.

Referring briefly to the drawing:

Fig. 1 is a View of the front of the device with sliders partly slid.

Fig. 2 is a View of the back or reverse side of the device.

Fig. 3 is a transverse sectional view taken in a plane represented by line 33 in Fig. 1 of the drawing.

Fig. 4 is a longitudinal sectional View taken in planes represented by line 4-4 in Fig. 2 of the drawing.

Fig. 5 is a view of the rear ci the front panel taken as a sectional view in a plane represented by line 5--5 in Fig. 4 of the drawing.

Referring more in detail to the drawing, the embodiment selected to illustrate the invention is shown as comprising spaced front and back panels or walls l and 2 joined at their upper and lower edges by spacer strips 3 and d to form a flat envelope-like tube open at both ends `and within which are slidable front and back sliders 5 and S. Normally when the sliders are full-in their ends coincide with the ends of the walls I and 2, and hence the latter are provided at both ends with notches or cut-outs 'I and 8 for facilitating the grasping of the end portions of the sliders by the thumb and finger to pull and slide the sliders.

The slider 5 has on its iront face series of value indicia 0, I0 and Il, such as numerals capable, as slider Ei is slid, of showing through windows I2, I3 and I4 provided in the front wall I. In the embodiment selected to illustrate the invention, and referring in particular t0 Fig. 1, the upper row of numerals 9 represents miles per gallon; the lower row I I represents the cost in dollars when operating at the rate shown by the numerals 9; and the intermediate row I0 represents the total number of gallons used at the rate shown in the row 9.

The back 2 is provided with a large window I5 through which may be seen resultant indicia, as later explained. Along an edge oi the window I5 is a series of indicative indicia I0 in the form of numerals with graduation marks Il corresponding thereto. On the rear face of the rear slider B is an arrow having its head I8 pointing toward the graduation marks Il, and a long shaft I9 which always forms a continuation in all slid positions of the slider 6 with an arrow tail 20 on the rear face of the wall 2, as shown in Fig. 2.

On the rear face of the front wall I is a triangular chart of indicia 2 I, as numerals, located opposite the window i5. These numerals are arranged in crossing or traversing rows so that 'Each indiciurn is common to two rows of indicia and the rows traversing in one direction are at an acute angle to the rows traversing in the other direction, and all rows at acute angles to the line of slide of the sliders.

The sliders 5 and E are respectively provided with elongated, inclined windows 22 and 23 in in the form of slots, as shown in Fig. 2. The window 22 is capable of exposing the inclined rows of numerals which run downwardlyr to the left, as viewed in Fig. 5, when the slider 5 is slid. The window 23 is capable of exposing the inclined rows of numerals which run downwardly to the right, as viewed in Fig. 5, when the slider B is slid. Since the windows 22 and 23 Cross each other, there will be at each relative setting of the sliders 5 and 6 a common window 24 (Fig. 2) which will expose only one indicium or numeral common to the two crossing rows of indicia or .numerals of the chart lying opposite the windows 22 and 23. Hence the window 24 is virtually a sliding or shifting window, sliding up and down the slots or windows 22 and 23 as the sliders 5 and 5 are relatively slid.

While the device has been described as having joining strips 3 and 4 at the edges oi the walls l and 2, as shown in Fig. 3, it will be understood that the walls l and 2 may be portions of a sheet or tube attened to form a sort of flat envelope with the folds or joints at the edges of the walls.

To show the use of the device, it will be assumed, for illustration, that the car, the operation of which it is desired to improve, maires 12 miles per gallon of fuel. 'I'he user slides the sliderl 5 to expose the indicium "12 in the window l2 (Fig. 1). In window i3 will appear the numeral 416 showing that at the rate of 12 miles per gallon of fuel there has been 416 (disregarding fractions) gallons of fuel used in 5,000 miles.

The total cost of that is $79.00, as shown in window i4, when the fuel has the average cost of 1.9 per gallon.

If it be desired to obtain better mileage, such as 16 miles per gallon, the user turns over the calculator and slides the slider 6 to bring the arrow head i8 in register with the graduation Ina-rk I1 corresponding to the desired mileage numeral value 16, and then reads in the window 24 that at the rate of 16 miles per gallon there will be a saving of $20.00 for the total mileage of 5,000 miles.

The total cost of $59.00 when operating at a rate of 16 miles per gallon may, of course, be obtained directly from the front of the calculator by simply sliding the slider to expose the value 16" in the window l2, and reading the value 59 in window I4, but there would be the further necessity of subtracting 59 from "79 to obtain the saving of $20.00 indication. The present invention gives this saving immediately on the reverse side of the calculator by simply sliding slider 5 with the arrow head i8 at the value 16. What is important is the quick and easy indication of the saving made, without the necessity of making the usual calculation.

While I have herein described and upon the :drawing shown an illustrative embodiment of the invention, it is to be understood that the invention is not limited thereto, but comprehends other constructions, details, arrangements of parts, and features, without departing from the spirit of the invention.

Having thus disclosed the invention, I claim:

1. In a calculator of the character disclosed, a holder having arithmetical indicia on a Wall thereof and a window in another wall thereof and opposite said indicia, and two relatively slidable members movable between said indicia and said window, said members having elongated windows opposite said window and said indicia and disposed to traverse each other to provide a shifting window common to said elongated windows to selectively expose therethrough an indiciuin of said indicia, said holder having further arithmetical indicia adjacent said window, and one of said slidable members having an indicator selectively registrable with said further indicia.

2. In a calculator of the character disclosed, a holder having arithmetical indicia on a wall thereof and a window in another wall thereof and opposite said indicia, and two relatively slidable members movable between said indicia and said window, said members having elongated windows opposite said window and said indicia and disposed to traverse each other to provide a shifting window common to said elongated windows to selectively expose therethrough an indicium of said indicia, said elongated windows each being at an acute angle to the line of movement of said members.

3. ln a calculator of the character disclosed, a holder having arithmetical indicia on a wall thereof and a window in another wall thereof and opposite said indicia, and two relatively slidabie members movable between said indicia and said window, said members having elongated windows opposite said window and said indicia r, and disposed to traverse each other to provide 35 a shifting window common to said elongated windows to selectively expose therethrough an indicium of said indicia, said elongated windows being at an acute angle to each other and each at an acute angle to the line of movement of said members.

In a calculator of the character disclosed, a holder having arithmetical indicia on a wall thereof and a window in another wall thereof y and opposite said indicia, and two relatively slidable members movable between said indicia and said window, said members having elongated windows opposite said window and said indicia and disposed to traverse each other to provide va shifting window common to said elongated windows to selectively expose therethrough an indicium or" said indicia, said indicia opposite said window being arranged in rows that traverse each other with each indicium being common to two traversing rows, said holder having indicative indicia adjacent said window, and a slider having an indicator selectively registrable with said indicative indicia.

5. In a calculator of the character disclosed, a holder having arithmetical indicia on a Wall thereof and a window in another wall thereof and opposite said indicia, and two relatively slidable members movable between said indicia and said window, said members having elongated windows opposite said window and said indicia and dissed to traverse each other to provide a shifti window common to said elongated windows to selectively expose therethrough an indicium of said indicia, said indicia opposite said window being arranged in rows that traverse each other with each indicium being common to two traversing rows, the rows traversing in one direction being at an acute angle to the rows traversing in the other direction.

HAROLD B. ANDERSON. 

